Can you hear the difference between a sine wave and a square wave?
Sine waves and square waves sound completely different, don't they? Well maybe not always. As the frequency rises, they become more and more similar. This video explores the differences and similarities between sine waves and square waves. And it will test your hearing!
Sine waves and square waves sound completely different, don't they? Well maybe not always. As the frequency rises, they become more and more similar. This video explores the differences and similarities between sine waves and square waves. And it will test your hearing!
Browse oscilloscopes on Amazon...
Browse function generators on Amazon...
Transcript
Sine waves and square waves. They sound different don't they? The square wave is bright and maybe a little harsh where the sine wave is rounded and mellow.
So you'd think you could easily tell the difference between a sine wave and a square wave. Well, as I'll show you in this video, that might not always be so. Here's a preview...
[Audio]
Well that was obvious. The sine wave and the square wave sound completely different. I'm going to show you how things can change as the frequency gets higher.
Don't forget to subscribe and click the bell to get notified every time I upload a new video.
First things first... How did I set this up? Well firstly I generated the waveforms digitally so I've got perfect square waves and perfect sine waves inside my digital audio workstation software but then they go through the output of my audio interface to the oscilloscope so the oscilloscope is showing what comes out of the audio interface.
So this accounts for some things you'll see on the screen of the oscilloscope. Firstly the tops and bottoms of the square waves - You'll notice that they're slanted. The reason for this is because of the high-pass filter in the output of the audio interface. That's to get rid of frequencies below the normal human audio range which aren't any use to anybody. And secondly you'll see some ringing just after the transitions from low to high and high to low. This is caused by the filter - The low-pass filter in the digital-to-analog converter which gets rid of frequencies which are above the range of human hearing, which once again aren't of any use to us.
I could have used a function generator to generate a really clean square wave which would look great on the oscilloscope. The problem with this however is that's not what you're going to hear. You're going to hear the signals coming from your audio interface or the audio output of your computer. So therefore you're going to hear these slanted tops and bottoms and the ringing as well. So what you hear corresponds very well to what you see on the screen. If I'd used a function generator that wouldn't be the case. Maybe I'll use a function generator in a future video. We'll see how it goes. Leave a comment if you'd like me to do that.
Okay let's dive into the video...
I am going to demonstrate the difference in sound texture between a square wave and a sine wave and show how they become subjectively increasingly similar at higher frequencies.
I'll play a signal that alternates between square wave and sine wave starting at 100 hertz. You will hear the difference clearly.
[Audio]
As you can hear, the square wave has a very much brighter and harsher tone compared to the sine wave which is very smooth. The levels have been set to the same RMS values so that both waveforms should be subjectively equally loud.
Now I will increase the frequency to 1000 hertz or 1 kilohertz. As I continue to increase the frequency I will adjust the timebase control of the oscilloscope so that you can see the shapes of the waveforms clearly.
At 1 kilohertz the square wave and the sine wave still sound very different to each other. I will increase the frequency in 1 kilohertz steps.
2 kilohertz
3 kilohertz
4 kilohertz
At this point you will probably start to hear both waveforms as being very similar apart from a small difference in level but I will explain in a moment. Let's move more quickly through the frequency range...
6 kilohertz
8 kilohertz
10 kilohertz
12 kilohertz
At this point both waveforms sound pretty much identical. The reason for this is that the brightness of the square wave is caused by its harmonics. Where a sine wave only has one frequency component - its fundamental - the square wave has the fundamental and harmonics at whole odd-number multiples of the fundamental frequency.
So in a 100 hertz square wave you hear frequency components of 100 hertz, 300 hertz, 500 hertz, 700 hertz and so on all the way up the frequency band. As you can see in this spectrogram.
When we get to a fundamental frequency of 4 kilohertz however the next frequency component, which we call the third harmonic, is at 12 kilohertz. Many people can't hear frequencies as high as this.
At a fundamental frequency of 8 kilohertz the third harmonic is at 24 kilohertz, which hardly anyone is capable of hearing.
It is also worth saying that digital audio sampled at 44.1 kilohertz, which is common, can't reproduce 24 kilohertz either. A sampling rate of 96 kilohertz was used to make the original recordings here to show on the oscilloscope to allow a margin of safety.
So as the frequency increases the harmonics of the square wave become inaudible leaving only the fundamental. So at a high enough frequency it sounds exactly the same as a sine wave.
Finally let me explain the slight differences in level. Well if the harmonic components of the square wave are being lost at very high frequencies, the overall level will therefore be a little lower.
You might also notice some ringing in the square wave signal. This is probably being created by filtering in the digital-to-analog converter. The ringing frequency is around 46 kilohertz so it is well above the audio band.
The oscilloscope, by the way, is specified up to 20 *megahertz* so we can expect it to be completely clean in the audio band.
In summary, at increasing frequencies a square wave begins to sound more and more like a sine wave. So there you have it.
A square wave sounds pretty much like a sine wave at higher frequencies. It's all part of the fun of audio and I love it.
Don't forget to subscribe and click the bell to be notified every time I upload a new video, and of course there are other Audio Masterclass videos to enjoy.
I'm David Mellor, Course Director of Audio Masterclass. Come and visit us at AudioMasterclass.com and take a look at our range of courses in Music Production and Sound Engineering, all online.
Thank you for listening.
Comments on this video
You can comment on this video at YouTube
You can comment on this video at YouTube
David Mellor
David Mellor is CEO and Course Director of Audio Masterclass. David has designed courses in audio education and training since 1986 and is the publisher and principal writer of Adventures In Audio.
@SubroOrbus replies to @AudioMasterclass: wat
@colourbasscolourbassweapon2135 replies to @AudioMasterclass: The Square wave is basically just full of sine waves in a Frequency harmonics construction
@colourbasscolourbassweapon2135 replies to @AudioMasterclass: well anyway i'm going to play with my analog moog synths i got two hardwares
@chasecampan-thornburg1721: Thanks for this!
@jt5678: It's interesting to notice that the square waves appear to begin and end exactly at the inflection points of the sin waves; that is, the individual square waves begin and end where the sin waves change from concave up to concave down. Although, I suppose this only makes sense... As an interesting side note, these points can be mathematically calculated by taking the second derivative of the sin function, setting it equal to 0, and solving for (in this case) 't', though a sin function will have infinitely many. Only the first couple points are necessary as the inflection points of sin, and thus, the structure of the square wave will repeat on a given period. Cool beans, thanks for the visualization.
@x2mars: Damn! I couldn’t hear 👂 the 12 k 😢
@emiletetrt: After about 6kHz both of the signals were identical when hooked on my own scope :)
Funny to see we both use HAMEG scopes. I've the HM203-6 scope, however the line doesn't hit the edge of the display without using the x-mag button, stops about one div off each side.
@SoundAround-gr2xi: "high-pass filter of the audio interface"???? I think it is low-pass filter (antialiasing filter of DA converter) .
@SoundAround-gr2xi replies to @SoundAround-gr2xi: Oh now I get it, to get rid of DC unit (voltage), means frequencies below 10 or 20 Hz.
@AudioMasterclass replies to @SoundAround-gr2xi: Did I say that? Yes of course it is low pass. DM
@Garfield_Minecraft: My ear aw!
Is this what dog hear?
@KainniaK: Around 3 kilohertz my cat ran around and jumped in front of a car.
@Rockapotamus91: So is it true that pre/post ringing isn’t audible at all on any type of filter because it’s happening above what we can hear?
@glenharland5287: At 100hz I can hear the square wave but not the sine wave. Is it my speakers or my ears?
@AudioMasterclass replies to @glenharland5287: You're hearing the harmonics of the sine wave. DM
@toddh7266: Very well explained, Sir!
@sukhbirsingh8053: 2:17
I thought of "DX entrance music"
@YoureNotGettingMyNameDolan: This video explains very well what I've noticed when messing around with my signal generators and audio amplifiers, I thought this was from me not having a musical ear or from me not constructing my signal generators well enough. 😄
@didyoutryaltf4: the difference is that a sine wave is sine and a square wave is square
@stefansynths: Very interesting that the 10kHz square wave showed multiple lines. That's because 10kHz doesn't evenly divide 96kHz, while 6kHz, 8kHz, and 12kHz do. So each cycle of the 10kHz square wave has 4.8 samples low and 4.8 samples high. But it can't subdivide samples, so it will be either 4 or 5 samples each time. The first integer multiple of 4.8 is 5, 4.8 x 5 = 24. So every 5 cycles of the square wave it completes a cycle and comes back to where it started. Looking closely, there are 5 individual lines.
I worked this out before you said you were using 96kHz. I figured you were using 48kHz, the math works out the same. You definitely weren't using 44.1kHz or 88.2kHz or anything else like that.
@sreeharish6533: @Audio Masterclass I have a question.
Why does low hertz sound low.
What I mean is - in my phone i have a frequency generator app, keeping the volume of the phone constant. When i increase hz from 20hz to 2k hz why does the sound increase?
@AudioMasterclass replies to @sreeharish6533: 1) The frequency response of your ears. 2) The ability of your phone to output low frequencies. DM
@sreeharish6533 replies to @sreeharish6533: @Audio Masterclass one last question, if hit the fork hard or if i hit the fork softly.
In both the scenarios will the fork vibrate at same frequency?
@magicstix0r: The ringing isn't caused by filtering. It's caused by a fundamental law of nature.
A "true" square wave requires an infinite number of harmonics.
Even if you were to create the square wave algorithmically through the equation sin(2* pi * freq * t/nyq) > 0 ? 1 : 0, to actually play it back the speaker driver would have to move at infinite speed at the square wave's edges and stop infinitely fast, which is of course impossible.
Thus a square wave not a band-limited signal and can't be recreated by sampling.
It's called "Gibb's Phenomenon," and it's the kind of thing you'd expect a "Masterclass" to know about...
It's also the reason things like the Heisenberg uncertainty principle and the Casimir effect exist...
@Damnzz: 04-03-2023
12 19 uur dit zijn nu de gesprekken op LFG over mij: wij zorgen ervoor dat hij nooit meer in dit land komt
@adammachin: I can still hear 12
@you_just: haven't finished the video, but i'm going to make a prediction that the reason that they begin to sound the same is because the 1kHz square wave is just made up of a 1kHz sine wave with a bunch of higher frequencies added on. as the base wave gets higher, the higher frequencies eventually shift out of the range of human hearing.
@teashea1: very informative
@cassettedisco6954: Amigo acabo de encontrar tu canal y es genial, muy educativo y entretenido muchas gracias, saludos desde México 🇲🇽
@francobuzzetti9424: i didn't heat anything in 6khz but i did on 8khz , i think it matches my tinnitus..
@zaxolotl: I feel very smart cause I actually picked up on this happening on my own while making chiptune! The explanation however makes so much sense!! I just never considered it
@whitex4652: Completely false. You are an idiot. There is no square wave on this universe. Your conclusions and statements are utter bullsh*t.
@peekpen: This guys a natural electronic engineer but in rock n roll.
@samuelcameron9353: This is very helpful but I can not find a reference to a very obvios point. If people are listenting to this on typical laptops peakers then the opportunity to hear what is being presented is going to be severely hamperedd by the roll off at higher frequencies.
People are goong to be biased towards hearing no difference between different waveforms due to this and at higher levels
there will be no sound at all in some cases.
I suspect that even basic smartphones have a better presentation at higher frequences than many brand name laptops.
@AudioMasterclass replies to @samuelcameron9353: You're exactly right of course. I used to warn against listening on laptop speakers but I came to a point a while ago where I thought that anyone watching a pro audio channel would know this. But I might go back to the warning again. DM
@Fritzafella: This was actually really fascinating and very well put together!
@Sumatoa: It is normal if i can hear the difference between the sine and the square wave at 12khz ?
@mage3690: The "ringing" is actually an artifact of creating lower pitch square waves by adding progressively higher and higher multiples of sine waves together, which is probably where the harmonics come from as well. It's something Fourier discovered while trying to explain the phenomena of how heat dissipates through different temperature rods before finally coming up with the now-famous Fourier transform.
@inciseinfinity replies to @mage3690: indeed, it's called the Gibbs phenomenon and it is present in all waveforms that has a finite discontinuity (a jump in amplitude) like the square wave, but also the saw wave too.
@quaccn replies to @mage3690: he’s not wrong in sayings it’s because of the low pass filter. As you continue to add sine waves, it gets closer to a perfect square wave, so when a low pass filter is applied, it becomes less like a square as it loses the higher frequency sine waves, creating that “ringing” phenomenon.
The square wave isn’t being created by layering sine waves, but every sound can be expressed as many sine waves put together, and using filters, sine waves of different frequencies can be taken out
@Blox117 replies to @mage3690: a speaker cannot produce square waves, because it would require the diaphragm to move infinitely fast or at least extremely fast compared to a sine wave.
@triple_x_r_tard replies to @mage3690: but it isn't. because these waves aren't created using additive synthesis. ya dunce.
@mlvpssai: I can’t hear the 12 KHz. Is that a significant clinical observation!
@Vmaxfodder: Which is more efficient??
@jckstudios7693: Talk in a square wave, I mean replicate the pitch of your speech so it sounds like it
@Tohidplays7155: 2:10 Yes, Please
@KavasPVP: The problem is that it's not a perfect square wave, there's some sine element to it and you can even hear it more and more as the frequency increases.
@urosrakic6900: I personally love square and sawtooth waves, since they are fun and you can hear the tone clearly (due to harmonics and overtones). But, I hate sine wave, since it is plain boring + at lower frequencies, you have to turn volume up in order to hear the tone (if the frequency of the tone is 27,5 Hz, the sound pressure has to be around 70 dB for sine tone, which means that you have to turn volume up (and with that, you're risking to damage your hearing)). But with the sawtooth or square waves, you can clearly and without turning volume up hear 27,5 Hz sound. Sine wave is boring, bland and simplistic, it doesn't have any variety. Sawtooth and square waves are more interesting and fun.
@RahulSharma-oc2qd: Amazed by the details given in a video of 9 mints. Appreciate the clear explanation on the topic. Thank you. I am getting into Vehicle Acoustics field and this would help me to look things differently.
One question related to content, I am looking for such detailed explanations on harmonics in Freq spectrum. It’d be great if I could get some information on that.
@AudioMasterclass replies to @RahulSharma-oc2qd: https://www.audiomasterclass.com/one/understanding-audio DM
@NC8ED: Interesting no audio at or above 8 Khz Time to throw the test CD into the removable drive. I can still hear the 15,750 on my old kitchen TV.
@UsernameXOXO: Your cutting software makes you look like a deepfake. Are you a deepfake? If not, you're a human that used autotune but for picture.
@ian2armannduccio: Dave, or whatever your name is (did you even introduce yourself?) it's not "Don't forget to subscribe", as you keep repeating, it's "Please subscribe to my very very dull broadcast, if you've absolutely nothing more interesting to do, like cleaning the catbox".
@rebelgurl7948: So does this mean in a PEMF mat that has sine wave only that by lowering your frequency from 3 gauss or 1-30 frequency to the lowest setting you can get a square wave?
@AudioMasterclass replies to @rebelgurl7948: It would be the other way around. If your mat uses a square wave and you can set the frequency high enough it will feel like a sine wave. That's my hypothesis, but it would need an expert in this kind of therapy to advise reliably. DM
@iampuzzleman282: Cant hear anything beyond 8 k
hz
@jds1906: Funny... Either the man does not Blink his eyes or we are blinking in sync, and can't tell when he does, lol...
@GreatBigBore: But where do the harmonics come from? And shouldn't they be visible on the scope? Or maybe it's zoomed in too much to see them? Great video, thanks!
@AudioMasterclass replies to @GreatBigBore: You would need a mathematician to explain where they come from - try https://en.wikipedia.org/wiki/Square_wavehttps://en.wikipedia.org/wiki/Square_wave - All I know is that they are there. You can't see them on an oscilloscope but a spectrograph will show them clearly (in a square wave). DM
@SebastianJanowski replies to @GreatBigBore: @Audio Masterclass You could also plot an FFT of the waveform. I don't miss calculating those by hand.
@mage3690 replies to @GreatBigBore: If you look into the way Fourier came up with his Fourier transform, it suddenly becomes clear. Square waves can be made by adding together progressively higher and higher multiples of sine waves. 3 blue 1 brown has a fantastic video on it. The ringing he pointed to near the end is actually an artifact of that process.
@drippyinfinities: 1:49 – the background is cursed!
@TintomaraAriadne: They didn’t sound identical at all to me. But I do hear higher frequencies than the majority. Interesting video!
@TintomaraAriadne replies to @TintomaraAriadne: @MF Nickster then I don’t know why they didn’t sound identical, but they didn’t.
@Charlie-qn4my: That was interesting, thanks. Although, my cat wasn't pleased
@qwerty_____146: thank you, dear.
@MotherBEEOfficial: hello american i am korean? {Amazing}
@sandi21515: How I wish I understood any of this. My dad was an electrical engineer who breathed this stuff.... and then there's me. ~sigh~
@sarvagyagupta1744: I wonder how would a constant sound like? Something like y=10. I guess we won't hear anything because there's no frequency.
@AudioMasterclass replies to @sarvagyagupta1744: If you add a constant to an audio signal you get a DC offset. That will cause switching clicks and in the (probably) worst case could bias a loudspeaker cone causing distortion on positive or negative peaks, depending on the sign of the constant. That's my first thought off the top of my head but I'm sure there's more to it. DM
@codebeat4192: It is easy to explain, the smaller width and distortion at the top of the square wave make them more similar because the angle to go up and fall down of the sine wave is sharper. The sine wave starts to look more like a square wave at higher frequencies because the width is smaller and the top angle is sharper. Actually both start to look more like a sawtooth.
@LeeLightfoot: super stuff
@AudioMasterclass replies to @LeeLightfoot: Thank you. DM
@ATLHooligan: Cool, thx my British friend.
@AudioMasterclass replies to @ATLHooligan: You're welcome, typed in a vaguely northern English accent. DM
@tomypower4898: Yes need to make AI, I got one for ya!
@troelshansen6212: Just have to put on my physicist hat here for a moment: The Ringing in the signal is what is known as Gibbs phenomenon. It is an intrinsic artifact that shows up when you do a finite fourier series decomposition of a discontinuous (ei it has a sudden "jump" from one amplitude to another) signal. No piece of electronic equipment can generate a "perfect" square wave, because that would require an infinite number of sine waves of increasing frequency and decreasing amplitude added together. We have to put in a frequency cut-off somewhere when creating an actual physical signal, and as you pointed out, the available frequency range of the playback device is usually the limiting factor. But as soon as we cut off our fourier series of the square wave, mr Gibbs pops up.
@AudioMasterclass replies to @troelshansen6212: Thank you for your input, which I appreciate. There was some discussion of this earlier, if you look down the comments for SpyProductions. As for generating a perfect square wave, adding up sine waves would be a long-winded way of doing it and it's simpler to flip from low to high to low etc. That of course is also imperfect due to the rise time, but a decent function generator should be able to create a square wave that is good enough for any audio purpose. I doubt whether that would prevent Mr. Gibbs from popping up though. DM
@jasonisbored6679: Very professional demonstrations and video, and very mindful of the viewers' constraints! Much appreciated by a curious physics student.
@AudioMasterclass replies to @jasonisbored6679: Thank you. As a curious physics student you might also wonder whether the square wave is the only waveform I could have used for this test. DM
@David-sw3on: Well, In the beginning I was honestly listening with intent, but I had to start the vid over when I suddenly realized I was actually wondering when this man was actually going to blink, if ever!🤔 Haha...to be continued👍😉 (and I'm sorry oh blinkless one..but if theres any consolation, I did subscribe to you!)
@marshalcraft: At 6khz I have permanently damages your brain, muahahahaha
@aluisious: This is how I know I am ready to turn 40, when I bought fancy headphones, started worrying about what my amps are doing, and an oscilloscope and some webpages about measuring output impedance later, here I am, worrying about how much the amps are ringing.
@AudioMasterclass replies to @aluisious: The ringing you see here is way above the range of human hearing, and when you do turn 40 your high-end will decline anyway. So, nothing to worry about! DM
@shawnli4746: if you can hear 10 kilohertz you must be very young ;)
@ryanjoshuacalo9146: Never have I ever wanted to hear a function generator from youtube in my entire life.
One video clip please
@AudioMasterclass replies to @ryanjoshuacalo9146: You should probably avoid this link https://www.youtube.com/results?search_query=function+generator
@coryshinn5764: Does this apply to other timbres other than square?
@AudioMasterclass replies to @coryshinn5764: The triangle wave also has only odd-numbered harmonics, so the test would be similar. DM
@phauloriquelme2657: 3:19-3:28 Censor Beep
@Purple431: How about a sawtooth wave?
@AudioMasterclass replies to @Purple431: A sawtooth wave sounds more similar to a sine wave than a square wave does but at lower frequencies the harmonics will be audible. For a 5 kHz square wave, the next harmonic after the fundamental is 15 kHz and is probably inaudible to most people, so the square wave will sound like the sine wave. A sawtooth wave at 5 kHz will have a harmonic at 10 kHz, which probably is audible. So at that frequency and lower the sawtooth wave will sound different to the sine wave. At 7.5 kHz, all three will sound the same, assuming the listener can't hear 15 kHz and above. That's my long answer to your short question, but the best thing to do will be to try it for yourself. Bear in mind that any distortion in your listening system may confuse the issue. DM
@erwanregy: this man never blinks
@AudioMasterclass replies to @erwanregy: That's correct. Now if only you were the first person to say that...
@Nerd3927: A square wave formula is A = sin a + 1/3 sin 3a + 1/5 sin 5a + 1/7 sin 7a and so on. The higher the tone, the harmonics start going out of your hearing spectrum. 4kHz x 3 = 12kHz so for mee that is the end at 52.
@creenus_beenus: me when im gaming
@snakewhitcher4189: Just use whatever sounds best to you. None of us are ready for control on that level. Except for one guy, and he used that level of control for evil. He explored people's heads.
@snakewhitcher4189 replies to @snakewhitcher4189: Just to watch them die
@thraxmystica: 5:00 my ears are bleeding
@connorbrown7455: Very educational video! The explanation helped me understand why a sound I was producing sounded like it was ringing.
On a totally unrelated side note, one suggestion I would make would be to try blinking a few times a minute while recording. Not blinking can be a bit off-putting for a viewer, though they might not consciously process it.
@AudioMasterclass replies to @connorbrown7455: As you can see, I'm not a natural presenter. And now I have to think about blinking as well... DM
@connorbrown7455 replies to @connorbrown7455: @Audio Masterclass Well I think you did great overall! That's just a suggestion for a slight course correction. I'm definitely not trying to trip you up. 😂
@Ccyawn123: Square waves make better sounding electronic organs than some waves 😆
@Twilightsummerbreeze: Do you think our body, or electrical body, (aura?) acts as a filter to all the frequencies surrounding us? That frequency seems to be like tinnitus. Because if you listen, you can hear all that static in your ears, and perhaps illnesses get in by a dissonant tune that wasn't filtered properly. What do you think?
@AudioMasterclass replies to @Twilightsummerbreeze: These are topics that I'm not qualified to comment on. But if tinnitus is an issue for you then you should consider consulting an audiologist. DM
@houdinididiit: Very interesting. It's the same with tempo and rhythm in some ways. (I.G.) As tempo increases for a jazz ride cymbal pattern based on the the triplet, it 'flattens out' and becomes indistinguishable from sixteenth notes. (Basically, as the gaps in time shorten, there isn't enough space to create the triplet that would be perceived by the ear.) This is same experience here except... we have frequencies which obviously get faster as you go higher and also 'flatten out'. Or sound more 'rounded out'. It's kind of like a musician's version of relativity. :-P
@AudioMasterclass replies to @houdinididiit: Agreed. It's also interesting with an analogue oscillator to set a square wave to around 1 Hz, which will sound like clicks. Then increase the frequency slowly. The clicks get faster, then at some point above 20 Hz they will start to sound like a musical tone and the individual clicks will disappear. DM
@matthewai32: Is it just me or does this guy never blink? Overall great video though!!
@AudioMasterclass replies to @matthewai32: I was bitten by a radioactive spider and this is the superpower I got. DM
@SouthShoreSonics: The 12khz sound the same, as is not heard. At 57 I do not think I can hear much above 8Khz
@alexanderdvanbalderen9803: "low frequency sine waves may not be audible on laptops" god I was panicking
@camthesaxman3387 replies to @alexanderdvanbalderen9803: Completely inaudible on my phone speaker as well.
@WolpplayzNAUTTP: Stop you're killing my ears.
@user-dt6rn3ud5z: 👍🏾
@ecciq: Hey, my friends aaron likes your face!
@cgsrtkzsytriul: Isn’t there also the fact that the speaker has to physically move through space to create sound waves, and it is simply unable to move fast enough to produce a true square wave? If a speaker were designed differently to produce much greater force to overcome air resistance at higher frequencies we might get a true square wave.
@cgsrtkzsytriul replies to @cgsrtkzsytriul: Also, maybe you’re running into the limit of your digital frequency generator. I forget the exact theory , but I’m pretty sure you can add enough higher frequencies to replicate any square wave, although you never get rid of the “bat ears” on the edge
@cgsrtkzsytriul replies to @cgsrtkzsytriul: Also, there may be a frequency limit on the propagation of square waves through air. Even if we had a machine that could produce a perfect square wave, the air molecules may not be able to move fast enough and it could get “rounded” to a sine wave.
@AudioMasterclass replies to @cgsrtkzsytriul: Q1: There's no such thing as a true square wave other than in a mathematical function. But if the tweeter of the loudspeaker can handle frequencies up to 20 kHz, then that's good enough frequency-wise for humans. Phase response would be a different issue that would affect the shape of the square wave but humans are not very sensitive to phase.
@AudioMasterclass replies to @cgsrtkzsytriul: Q2: The square waves were generated digitally in the DAW. A function generator would provide a better square wave but I explain in the video why I used digitally generated square waves.
@AudioMasterclass replies to @cgsrtkzsytriul: Q3: That's a good question that would take an acoustics specialist to answer fully. It is known however that high frequencies travel better in humid air than dry, so it could be a factor.
@bonbonpony: I can hear the difference up to 6 kHz. But this experiment is flawed, since your "square wave" is not really a square, which can even be seen clearly on your oscilloscope: due to filtering, most of the higher harmonics get filtered out and what's left is just a couple of regular sine waves mixed together. That's why they sound so similar.
@AudioMasterclass replies to @bonbonpony: The video covers this issue but I'll explain briefly. The waveforms are digitally generated and are output through an audio interface. This filters out frequencies above 20 kHz or so. This is why the square wave isn't exactly square. I could have used a function generator and the square wave would look square, but your audio output filters the high frequencies too, so what you hear wouldn't correspond with what you see. The way I did it here, what you see corresponds closely to what you hear. The similarity between the sine wave and square wave above 6 kHz or so is due to the harmonics being higher than most humans can hear, and above 7 kHz they are filtered out in the D-to-A convertor, and even if they were not filtered, you wouldn't be able to hear them. DM
@ATIHpss64HM: Can you hear the difference between sinewave and squarewave?
YES! THEY SOUND COMPLETELY DIFFERENT! BRUH WHAT KIND OF QUESTION IS THAT!?
@AudioMasterclass replies to @ATIHpss64HM: This is why you shouldn't comment before watching the whole video.
@ATIHpss64HM replies to @ATIHpss64HM: @Audio Masterclass oh.
@solarmonk: This is fantastic! David's eye contact is on-point - amazed he didn't blink once the entire video.
@AudioMasterclass replies to @solarmonk: I did all my blinking during the oscilloscope shots. DM
@chaoticsystem2211 replies to @solarmonk: @Audio Masterclass Blink twice if you were forced to listen to sine waves!
@gameauto1 replies to @solarmonk: 𝘾𝙤𝙣𝙜𝙧𝙖𝙩𝙯 oﾟ*｡o
／⌒ヽﾟ
∧∧ ／ヽ )｡*o
(･ω･)丿ﾞ￣￣゜
ノ/ / ｯﾊﾟ
ノ￣ゝ
@gameauto1 replies to @solarmonk: @Chaotic System 🎉
@JazzTigan: Pls make video about Pulse wave
@Naeromusic: Interestingly, at 6k+ the squarewave sounded more quiet than the sine wave
@AudioMasterclass replies to @Naeromusic: It's subjective. For me the balance between left and right on headphones isn't consistent all the way through. But it's mono, so it must be my ears. DM
@asapatheist: 6:44 a margin of safety? is this a British thing? are we hedge betting or doing physics?
@AudioMasterclass replies to @asapatheist: Sampling rate has to be at least twice the highest frequency you want to capture. It's maths. British maths https://en.wikipedia.org/wiki/E._T._Whittaker
@asapatheist replies to @asapatheist: @Audio Masterclass understand that, but specifically the term "margin of safety", here (in the U.S.) we say margin of error to expressing an amount of random sampling error.
@asapatheist replies to @asapatheist: margin of safety, in studio management, the percentage of sessions I can sacrifice during corona but still keep the studio open.
@AudioMasterclass replies to @asapatheist: @ASAP ATHEIST Perhaps it is British usage, but when I say 'margin of safety' or 'safety margin' I mean that it's over-engineered. So 44.1 or 48 kHz sampling is adequate for most purposes, but 96 kHz is technically better even through very few listeners will notice any difference. In this case, it helps preserve more of the sharpness of the corners of the square wave (which in analogue would not be a problem). As for 'margin of error', for me this would be related to statistics rather than audio so it isn't a phrase I'm likely to use, but now that you've mentioned it I'm tempted to try and work it in.
@sami_el3652: please i have an experiment of effect of hz in water what i need to use ?
@AudioMasterclass replies to @sami_el3652: This would be interesting but we have no expertise in sound travelling in water so it would be best to enquire elsewhere.
@mericet39: Your filter which removed high frequencies is removing some of the terms of the Fourier series which comprises the square wave. This effect is more noticeable for higher frequency waves, as more of the terms are removed. This is visible in the CRO. So part of the reason for them sounding more alike is that the resultant wave forms are more alike.
(and it seems my sound card stops at 12 kHz! Or at least I hope it's my sound card & not my ears!)
@AudioMasterclass replies to @mericet39: I'm going to politely disagree with you. This informal test works just as well in the analogue domain where the square wave can be clean up to and beyond 20 kHz, so it's what you can and cannot hear that makes the square wave sound like a sine wave at higher frequencies. The filtering visible in the oscilloscope is that due to the low-pass filter in the digital-to-analogue converter through which the digitally-generated sine and square waves are output. When an analogue version of the internet is available I'll be pleased to repeat the demonstration. Thank you for taking the time to comment, and P.S. It might be your ears! DM
@Moundain replies to @mericet39: I feel its aberration from filter
@snaigusas5963: Nice bass
@brianrodman1033: These videos would have been a lifesaver when I was first getting into synthesis and learning the essentials
@AudioMasterclass replies to @brianrodman1033: Thank you for your comment. It would be interesting to make a video on basic synth waveforms, VCA, VCF etc so I might put that on my list. DM
@brianrodman1033 replies to @brianrodman1033: Audio Masterclass that’s a great idea and would be very helpful for many people
@AdhamMGhaly: This is one of the best videos I have watched in the past year or so
@AudioMasterclass replies to @AdhamMGhaly: Thank you. We have some new material in preparation. We hope you enjoy it as much.
@jish40able: What dose it sound like on the Htz scale
@AudioMasterclass replies to @jish40able: This video - https://www.youtube.com/watch?v=vge0GmVqUXg - might answer your question.
@jish40able: How dose one figure this out??
@janji3190: Video: Can you hear the sine waves?
Me: Sine From Above-Lady Gaga
Sorry..hahaha *Last Song Syndrome
@bolulembut1132: there is a rumour about using modified sine wave to audio stuff like powered speaker will damage the device is it true?
@AudioMasterclass replies to @bolulembut1132: In a speaker with a woofer and a tweeter, the woofer handles most of the power. That's normal for speech and music. If you drive the speaker hard with a sine wave above the crossover frequency, or a square wave which is rich in harmonics, you could send the tweeter more power than it is designed for. The voice coil will partially melt, breaking the circuit, and there will be no output.
@bolulembut1132 replies to @bolulembut1132: @Audio Masterclass does this also apply/happen with line interactive UPS which is using modefied sine wave inverter?
@AudioMasterclass replies to @bolulembut1132: We don't have experience of this, but running audio equipment from a modified sine wave inverter doesn't seem like a good idea. To be sure, you might consider contacting the manufacturers of your equipment and see what they say. There's an interesting thread at https://www.reddit.com/r/audioengineering/comments/1m5c6t/pure_sine_wave_vs_modified_sine_wave/
@odealianaffairs9001: additive synthesis be like "bruh?"
@user-hd4wf5gq8r: I heard a power chord going from 2khz to 3khz to 4khz. Interesting.
@AudioMasterclass replies to @user-hd4wf5gq8r: It's what a lot of people have been searching for https://www.youtube.com/results?search_query=the+lost+chord
@lynnlo: Very nice video.
@AudioMasterclass replies to @lynnlo: Thank you. DM
@DavesGarage: Why does the background follow your head at 1:52? It's an edit of some kind, I just can't picture what you were fixing!
@AudioMasterclass replies to @DavesGarage: It's a flow transition in Final Cut Pro. When it works it's good. When it doesn't... well you have seen already. I've given up on that as you can see in https://www.youtube.com/watch?v=Ht3pMAkzums DM